Clinical longevity of amalgam replacing extensive direct composite restorations; Up to 13 years follow up

Background: Direct composite restorations are widely used to restore posterior teeth, with acceptable clinical performance. The replacement of inadequate, failed amalgam and composite restorations (due to fracture, secondary caries etc.) is a core occupation in dental practice. Many amalgam restorations are large and because of the undermining of cusps for macro mechanical retention these tend to fracture. There is restricted data on the performance of EDCRs (extensive direct composite restorations) involving one or more cusps.Therefore, there is a need for long-term follow up of EDCRs.

Main research question: What is the survival of extensive direct composite restorations involving one or more cusps after up to 13 years?

Design: This study has a cross sectional study design as one measurement per participant will be executed, however, these measurements will combined with other measurements from the previous study, which results in multiple evaluation times. Between January 2007 and September 2013, a total of 88 patients (57 women, 31 men; mean age: 51.6) received EDCRs (n = 118) in the posterior teeth. Population consists of adult, competent patients treated by Hans Scholtanus. These were evaluated up to 3,5 years. The present study will evaluate these restorations to a mean evaluation time of 13 years in a cross-sectional study design. Restorations will be scored using the modified FDI criteria by Hickel. Guidance and parafunctions will be checked. Restorations were scored as failed if any operative intervention was indicated for repair, partial or total replacement. Patient file will be checked on events. Outcome is the survival of extensive direct composite restorations after an mean follow up of 13 years.

Expected results: We expect a survival of around 90-95% of the composite restorations at a follow up of 13 years.

The survival of extensive direct composite restorations involving one or more cusps after up to 13 years will be sufficient

The primary outcome, the survival of the restorations, will be determined during an appointment on which the status of the restorations will be analyzed. Events will be noted based on the patient file. The secondary outcome, the FDI criteria, will be noted during the check-up appointment.There is only one measurement moment.

Not applicable